The invention relates to a spindle bearing for a two-for-one twisting spindle. More particularly, the invention relates to such a spindle bearing for a twisting spindle having a spindle rotor with a thread guide body and a spindle shaft rotatably mounted in a vertical arrangement by a lower bearing device in a bearing housing which can be fastened to a spindle bank and which has an upper bearing device for mounting a protective pot.
Conventional two-for-one twisting spindles comprise a spindle bearing, a driven rotor element and a protective pot for receiving the bobbin. Their spindle bearing has two bearing regions. In an upper bearing region, the protective pot is mounted on the rotor element so as to be rotatable relative thereto. Both the pressing forces of a tangential belt, which drives the rotor element by means of a wharve and the axially acting forces from the weight of the protective pot and the bobbin located therein are received in a lower bearing region. The roller bearings of the lower bearing region are designed for a conventional service life of about 50,000 hours. The roller bearings in the upper bearing region, on the other hand, are designed such that they do not reach this service life. After an operating period, which is between 20,000 and 30,000 hours, they are changed. The change can be carried out easily and rapidly as the upper bearing region is easily accessible after removal of the protective pot. This easy accessibility does not exist in the lower bearing region as the wharve is pressed onto the spindle shaft of the rotor element and therefore removal of the wharve is not possible. The roller bearings in the lower bearing region are therefore generally relubricated with standard greases to reach the service life of 50,000 hours.
A spindle bearing for a two-for-one twisting spindle is known, for example, from German Patent Publication DE-A-195 02 135. Ducts for supplying or removing lubricating grease are introduced into the bearing housing of the lower bearing region. A grease supply duct and a grease removal duct are allocated to each roller bearing. The grease supply duct and grease removal duct are in each case connected to a grease supply opening or grease removal opening. The grease supply opening or the grease removal opening forms the end of a horizontal duct on the outside of the bearing housing. Introducing duct portions with different directions, as shown in German Patent Publication DE-A-195 02 135 is complex and expensive in terms of production technology.
German Patent Publication DE-A-102 50 423 describes a generic spindle bearing for a two-for-one twisting spindle, the spindle rotor of which has a spindle shaft, which is rotatably mounted by means of an upper and a lower roller bearing. The bearing housing has a grease duct extending transversely to the rotational axis of the spindle rotor. In the interior of the bearing housing, the grease is distributed by means of a conical distributor ring and supplied to the bearings. To hold the distributor ring, a peripheral groove which is to be introduced into the spindle shaft is required. In the design of the bearing of German Patent Publication DE-A-102 50 423, with the distributor ring being used merely for grease distribution, compared to other known spindle bearings, an additional part and additional assembly outlay for this part are necessary.
Both German Patent Publications DE-A-195 02 135 and DE-A-102 50 423 show spindle bearings, in which the accessibility of the grease ducts when introducing the lubricant is impaired owing to their position. The possibilities of a compact configuration of the two-for-one twisting spindle are also limited by the position of the grease ducts half way up between the roller bearings of the lower bearing.